Heat retention barrel and vertical heat treatment apparatus provided with heat retention barrel

ABSTRACT

The invention provides a heat retention barrel and a vertical heat treatment apparatus provided with the heat retention barrel. The heat retention barrel is used for supporting the wafer boat and comprises a barrel body and a barrel base. The external rim of the bottom of the barrel body is located within the upper surface of the barrel base. The pollution of the particles in the heat retention barrel to the reaction chamber of the vertical heat treatment apparatus can be eliminated through the portion of the upper surface of the barrel base outside the external rim. The selection of the materials for the heat retention barrel can increase the heat retention and heat insulation effects as well as the use safety.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of China application serial no. 201010246622.4, filed Aug. 5, 2010. All disclosure of the China application is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to semiconductor heat treatment technology, and more particularly to a heat retention barrel and a vertical heat treatment apparatus provided with heat retention barrel.

BACKGROUND OF THE INVENTION

In a conventional vertical heat treatment apparatus having a wafer boat as a substrate holder, the heat retention barrel is positioned at the bottom of the heat treatment apparatus for supporting the wafer boat and preventing the heat radiating from the reaction chamber of the heat treatment apparatus downward. The high precision is required in the semiconductor manufacturing industry. The heat retention barrel is required to perform the following functions in addition to the function of supporting the wafer boat:

Firstly, the heat retention barrel is required to perform the function of heat retention, namely heat insulation, which can not only reduce the heat radiation and save energy, but also can prevent the components outside the reaction chamber being heated so as to maintain a normal working environment of the components and ensure the stability of the apparatus.

Secondly, the heat retention barrel is required to prevent the pollution particles entering the reaction chamber since the pollution particles may directly affect the processing effects.

Furthermore, the heat retention barrel is required to be safe in use as personal safety and equipment safety are greatly taken into account in the development of the process devices.

FIGS. 1 a to 1 c are cross sectional views of the conventional heat retention barrels.

As shown in FIG. 1 a, which is a cross sectional view of a conventional sealed heat retention barrel, the heat retention barrel is filled with heat insulation materials such as foam ceramic or ceramic fiber, and is vacuumed. Since the residual gas remaining in the sealed heat retention barrel may expand with heat during the process, an explosion may be caused by the expanded gas in the heat retention barrel. In addition, if the heat retention barrel is not completely vacuumed or air is induced into the heat retention barrel through the fine crack formed on the outer wall of the heat retention barrel due to the long-term use, the gas inside the heat retention barrel may also expand with heat to cause the explosion. Furthermore, the conventional sealed heat retention barrel has disadvantages of complicated processing structure and high cost.

FIG. 1 b illustrates a conventional heat retention barrel which can solve the problem of explosion. As shown in FIG. 1 b, an opening is formed at the bottom of the heat retention barrel, and a filter layer is provided at the opening to prevent the impurities inside the heat retention barrel entering into the reaction chamber with the gas flow. Although the pollution to the reaction chamber caused by the impurities inside the barrel can be reduced, the whole heat retention barrel is in the inner of the reaction chamber, thus the problem of the particulate pollution cannot be completely solved.

FIG. 1 c is a cross sectional view of a conventional plate type heat retention barrel. As shown in FIG. 1 c, a plurality of transparent round quartz chips welded on multiple quartz columns with certain spaces are processed to be opaque. Although the problems of the pollution and the explosion can be solved, the plate type heat retention barrel is not suitable for application in high-heat treatment equipments due to the poor heat retention effect.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been developed in consideration of the above situation and one objective of the present invention is to provide a vertical heat treatment apparatus, the apparatus comprises a heat retention barrel, a process tube and a reaction chamber, to eliminate the pollution caused by the particles inside the heat retention barrel to the reaction chamber of the vertical heat treatment apparatus.

Another objective of the present invention is to improve the heat retention and heat insulation effect of the heat retention barrel.

The other objective of the present invention is to enhance the use safety of the heat retention barrel.

To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the present invention provides a heat retention barrel comprising a barrel body and a barrel base, the external rim of the bottom of the barrel body is located within the upper surface of the barrel base.

According to the concept of the present invention, the barrel body is cylindrically shaped. According to the concept of the present invention, the heat retention barrel further comprises heat insulation material filled in the barrel body.

According to the concept of the present invention, the barrel base comprises at least one opening formed at the bottom of the barrel base and at least one filter disposed at the opening.

According to the concept of the present invention, the material of the filter is porous quartz. According to the concept of the present invention, the materials of the barrel base and the barrel body are quartz material.

According to the concept of the present invention, the quartz material is opaque.

The present invention also provides a vertical heat treatment apparatus comprising a reaction chamber, a process tube positioned outside the reaction chamber and a heat retention barrel positioned at the bottom of the reaction chamber; wherein the heat retention barrel comprises a barrel body and a barrel base, the external rim of the bottom of the barrel body is located within the upper surface of the barrel base; the process tube is connected with the portion of the upper surface of the barrel base outside the external rim to seal the reaction chamber with the barrel base.

In the present invention, the pollution of the particles in the heat retention barrel to the reaction chamber of the vertical heat treatment apparatus can be eliminated by sealing the reaction chamber through the portion of the upper surface of the barrel base outside the external rim tightly connected with the process tube. Furthermore, the heat retention and heat insulation effects as well as the use safety of the heat retention barrel can be improved by the selection of the materials.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

FIG. 1 a, 1 b, and 1 c are cross-sectional views of the conventional heat retention apparatus;

FIG. 2 is a cross-sectional view of the heat retention barrel;

FIG. 3 is a cross-sectional view of the vertical heat treatment apparatus provided with the heat retention barrel in one embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The vertical heat treatment apparatus and the heat retention barrel used therein of the present invention will be described in further details hereinafter with respect to the embodiments and the accompanying drawings.

Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings.

Referring to FIG. 2 which is a cross-sectional view of the heat retention barrel in one embodiment of the present invention, the heat retention barrel 40 used for supporting a wafer boat comprises a barrel body 1 and a barrel base 2. The barrel body 1 is cylindrically shaped and is inverted positioned on the barrel base 2. The bottom of the barrel body 1 is located on the upper surface of the barrel base 2 and a contact area is formed thereby. The external rim of the bottom of the barrel body 1 is located within the upper surface of the barrel base 2. The materials of the barrel base 2 can be quartz material, preferably opaque quartz material. The materials of the barrel body 1 can be quartz material, preferably opaque quartz material.

The heat retention barrel 40 may comprise heat insulation material filled in the barrel body 1, wherein, the heat insulation material can be quartz fiber, ceramic foam, ceramic fiber, etc., to achieve better heat insulation. The barrel base 2 comprises at least one opening formed at the bottom thereof and at least one filter 3 disposed at the opening. The filter 3 can be disposed inside the opening, above the opening, or below the opening to perform as the only path to discharge the gas and most impurities or particles inside the barrel body 1. The filter can be made of any porous heat resisting materials such as quartz or sintered ceramic. In an embodiment of the invention, the barrel base 2 comprises one opening.

Referring to FIG. 3, which is a cross-sectional view of the vertical heat treatment apparatus provided with the heat retention barrel in one embodiment of the present invention, the vertical heat treatment apparatus comprises a base supporter 10, a process tube 30 and a reaction chamber 20. The heat retention barrel 40 is positioned on the base supporter 10 of the vertical heat treatment apparatus, and the top of the heat retention barrel 40 partially contacts with the bottom of the reaction chamber 20. The process tube 30 is tightly connected with the portion of the upper surface of the barrel base outside the external rim of the barrel body 1, so as to seal the reaction chamber 20 with the barrel base 2. Due to the above structure, the heat retention barrel 40 will be blocked at the bottom of the reaction chamber 20 even the reaction chamber 20 is not connected therewith. Therefore, the whole heat retention barrel 40 will not be enclosed in the reaction chamber 20, leaving the barrel base 2 as well as the openings, namely vent holes, outside the reaction chamber 20. The particles inside the barrel 40 can be exhausted directly through the filters at the openings to the outside of the reaction chamber 20. Thus, the particles from the heat retention barrel 40 will not enter into the process tube 30 as well as the reaction chamber 20, the particulate pollution to the reaction chamber 20 can be eliminated and the quality of the semiconductor products highly requiring limited particles during the process can be ensured. Compared with the conventional heat retention barrel illustrated in FIG. 1 a, the heat retention barrel in the present invention increases the use safety. Compared with the heat retention barrel illustrated in FIG. 1 b, the heat retention barrel in the present invention eliminates the pollution of the particles in the heat retention barrel to the reaction chamber. And compared with the heat retention barrel illustrated in FIG. 1 c, the heat retention barrel in the present invention improves the heat retention and heat insulation effect.

In summary, the heat retention barrel and the vertical heat treatment apparatus provided with the heat retention barrel can eliminate the pollution of the particles in the heat retention barrel to the reaction chamber of the vertical treatment apparatus, and increase the heat retention and heat insulation effects as well as the use safety.

Although the present invention has been disclosed as above with respect to the preferred embodiments, they should not be construed as limitations to the present invention. Various modifications and variations can be made by the ordinary skilled in the art without departing the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be defined by the appended claims. 

1. A heat retention barrel comprising a barrel base and a barrel body, wherein the external rim of the bottom of the barrel body is located within the upper surface of the barrel base.
 2. The heat retention barrel according to claim 1, wherein the barrel body is cylindrically shaped.
 3. The heat retention barrel according to claim 1, wherein the heat retention barrel comprises heat insulation material filled in the barrel body; the heat insulation material is quartz fiber, ceramic foam or ceramic fiber.
 4. The heat retention barrel according to claim 1, wherein the barrel base further comprises at least one opening formed at the bottom of the barrel base and at least one filter disposed at the opening.
 5. The heat retention barrel according to claim 4, wherein the material of the filter is porous quartz or sintered ceramic.
 6. The heat retention barrel according to claim 1, wherein the materials of the barrel base and the barrel body are quartz material.
 7. (canceled)
 8. A vertical heat treatment apparatus comprising a reaction chamber, a process tube positioned outside the reaction chamber and a heat retention barrel positioned at the bottom of the reaction chamber, wherein the heat retention barrel comprises a barrel body and a barrel base, the external rim of the bottom of the barrel body is located within the upper surface of the barrel base; the process tube is connected with the portion of the upper surface of the barrel base outside the external rim to seal the reaction chamber with the barrel base.
 9. The vertical heat treatment apparatus according to claim 7, wherein the barrel body is cylindrically shaped.
 10. The vertical heat treatment apparatus according to claim 7, wherein the heat retention barrel comprises heat insulation material filled in the barrel body; the heat insulation material is quartz fiber, ceramic foam or ceramic fiber.
 11. The vertical heat treatment apparatus according to claim 7, wherein the barrel base further comprises at least one opening formed at the bottom of the barrel base and at least one filter disposed at the opening.
 12. The vertical heat treatment apparatus according to claim 10, wherein the material of the filter is porous quartz or sintered ceramic.
 13. The vertical heat treatment apparatus according to claim 7, wherein the materials of the barrel base and the barrel body are quartz material. 